Request FRR to be built with PIM support

[jogalt]

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Is your feature request related to a problem? Please describe. This is related to a limitation. I'd like to utilize opnsense as multicast traffic hub. Since pimd/igmp isn't compiled into the Opnsense frr package it isn't available.

Describe the solution you'd like A clear and concise description of what you want to happen.

Compile frr with the following flags:

--enable-pimd
--enable-igmp
--enable-multicast

Request additions to OPNsense os-frr plugin:

~Perhaps something under /usr/local/etc/frr/

Add kernel multicast routing support modules to /boot/:

ip6_mroute.ko (optional)
Add correct ip_mroute_load="yes" to /boot/loader.conf

Add multicast flag to IPSec interfaces:

IFF_MULTICAST     Supports multicast

Describe alternatives you've considered I don't have a valid alternative solution other than running frr barebones on a VM.

Additional context No other context. Just looking for full-featured multicast capability, if possible.

[Monviech]

https://docs.frrouting.org/en/latest/pim.html

That looks like a huge addition and FreeBSD only support SSM (Source Specific Multicasts) in that module.

If somebody wants to offer a PR we can look at it but it also increases complexity in a plugin that is already comolex and has quite some maintainance needs and technical debt.